code: def _cred1_adapter(composite, user=None, password=None):
      """Just a sample adapter from one user/pw type to another"""
      return dict(user=user + "_1", password=password + "_2")
  
file_path: datalad/datalad/downloaders/tests/test_credentials.py
imports: from unittest.mock import patch
  from datalad import cfg
  from datalad.api import Dataset
  from datalad.support.external_versions import external_versions
  from datalad.support.keyring_ import Keyring, MemoryKeyring
  from datalad.tests.utils_pytest import SkipTest, assert_equal, assert_false, assert_in, assert_raises, assert_true, ok_file_has_content, skip_if, with_tempfile, with_testsui
  from ..credentials import AWS_S3, CompositeCredential, GitCredential, UserPassword
label_desc: Use image node_id 4 for calling a global function with example usage: _cred1_adapter(composite, user, password) and returns: dict